<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <title>Document</title>

  <style>
    .box {
      width: 500px;
      height: 160px;
      margin: 200px auto;
      text-align: center;
      background-color: lightcyan;
      border-radius: 10%;
    }

    .item {
      width: 400px;
      margin: 5px auto
    }

    .item-span {
      display: inline-block;
      width: 50px;
    }

    body {
      background-color: rgb(214, 247, 255);
    }
  </style>
</head>

<body>
  <form action="/login" method="POST" class="box">
    <div class="item">
      <p class="item-span">用户名</p>
      <input type="text" name="name">
    </div>
    <div class="item">
      <p class="item-span">密码</p>
      <input type="password" name="password">
    </div>
    <button type="submit">登录</button>
  </form>
</body>

</html>